I am looking to provide constant current source, I am using a LM317 right now and it seems to be doing the job just fine. however I need to switch it between 2 or 3 different current levels. I can not seem to find any information on this or figure it out(I cant help but think I am missing something simple)
It needs to be switchable with a 3v3 micro controller, and the voltage coming out of the current source may need to be higher then 3v3(up to 5V depending on current selected).
Can anyone help me out or point me in the right direction.